I am given two events, A and B, and a new event C occurs, if and only if exactly one of A or B occurs. I need to prove;

So from the question, i got:

Is that correct and a good starting point? Or am i missing something out?

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- March 7th 2011, 02:34 PMMcooltaProbability Proof
I am given two events, A and B, and a new event C occurs, if and only if exactly one of A or B occurs. I need to prove;

So from the question, i got:

Is that correct and a good starting point? Or am i missing something out? - March 7th 2011, 03:23 PMPlato
From the second equation you can use:

. - March 8th 2011, 10:03 AMMcoolta
So i get:

Is that correct?

How do i go about getting rid of the union in the middle? - March 8th 2011, 10:20 AMPlato
- March 8th 2011, 10:49 AMMcoolta
Im confused to where the union has gone, from my original post?

Thanks for your help so far! - March 8th 2011, 10:56 AMPlato
Are you not proving that

That is what I thought you were doing. Is that not right? - March 8th 2011, 02:35 PMMcoolta
Yeah that is what im proving, im just confused from where the middle '+' has came from in the 4th post down, instead of a :

Why is it:

Instead of

Sorry if that is unclear, Thanks - March 8th 2011, 02:48 PMPlato
If you know that then you know that . Right?

Now

So the probability of that union is the**sum**of the probabilities.